A Forest Knolls fishery group has filed another lawsuit against the county, contending an ordinance regulating development near creeks doesn't protect endangered coho salmon.

The move by the Salmon Protection and Watershed Network handcuffs a county effort to enact interim regulations in unincorporated areas countywide.

In addition, it may revive a push at the Civic Center to revise the countywide plan in order to ease the document's prescription for 100-foot building setbacks near creeks and headwater drainage swales — a rule that curbs use of small rural lots in areas including San Geronimo Valley.

A county lawyer called the litigation a waste of time, but fishery advocates said it blocks development near habitat of an endangered species in dire straits.

"The ordinance allows excessive development along streams that are critical to the survival of endangered coho salmon," according to a statement issued by salmon protection activists and an allied advocacy group, the Center for Biological Diversity.

"Politicians and homeowners come and go but extinction is forever," said Teri Shore of Turtle Island Restoration Network, the parent organization of the salmon protection network, an organization "committed to protecting endangered salmon for the long term."

"Attacking an interim ordinance which has a life of two years is a colossal waste of time," said Steven Woodside, county counsel. "The court is not the place to solve the problem."

Because the county ordinance includes a "poison pill" stipulation saying it won't be enforced in the event of a lawsuit, the legal action leaves creek rules up in the air.

The fate of a building ban imposed in the San Geronimo Valley following another watershed network lawsuit remained uncertain as well, with Deputy County Counsel David Zaltsman, contending the ban was lifted when the interim ordinance was adopted last month. But Michael Graf of El Cerrito, representing the fishery activists, said the ban remains in place, adding that if there is disagreement about the matter, "the court is going to have to step in."

The interim creek ordinance, which was scheduled to take effect Dec. 28, was approved in an unusual hearing in which supervisors Steve Kinsey and Katie Rice, whose districts were most affected by the program, were barred from voting by state Fair Political Practices Commission lawyers who said the two supervisors had conflicts because they lived near creeks.

Supervisors Kate Sears, Susan Adams and Judy Arnold then agreed to impose interim creekside rules countywide pending more work on a permanent creek ordinance. The action followed years of study, false starts and an initial watershed network lawsuit. That suit has cost the county roughly $250,000 in staff and legal consultant fees so far.

"It is unfortunate that SPAWN has once again opted to go to the court rather than sit down and collaborate with all of the interested groups who care about our creeks, including streamside homeowners and property owners," Supervisor Adams said, adding she had not yet seen the lawsuit. "This two-year period offered us all the opportunity to collect data, incorporate best practices, map our streams and work collaboratively with all of the interested parties, including many of the other Marin environmental organizations."

Supervisor Sears also expressed regret at news of the lawsuit. The interim ordinance "was intended to provide an opportunity to examine how to apply stream conservation best practices to all areas of our county," Sears noted. "I'm disappointed that SPAWN has acted to stop that process and has chosen not to collaborate with our environmental community and property owners who see a positive way forward," she added. "This is the kind of zero sum thinking that stands in the way of actual progress."

Most local environmental groups, including the Marin Consevation League and Marin Audubon, supported the interim ordinance as a compromise after years of contention.

"Despite weaknesses in the interim ordinance ... the San Geronimo Valley Planning Group supported the ordinance and was looking forward to providing leadership in education and outreach activities in our community as well as strong participation with the county on new habitat restoration projects," noted group leader Jean Berensmeier. "Looks like we are on hold now with the ball in the county's court."

Niz Brown, a leader of the San Geronimo Stewards, a homeowner group, said the salmon network gets public funds from state fishery grants, then generates public expense by going to court.

"This lawsuit is just one more example of how disinterested they are about the people who live here, and are completely disinterested in all of the groups who want to work together to make our watershed favorable for all," Brown said.

But the fishery activists blamed the county for the sad state of affairs.

"Marin County has failed to put in place the streamside conservation protections that it promised to develop and implement years ago," said Deborah Sivas, a lawyer representing SPAWN who serves as director of the Environmental Law Clinic at Stanford. "Time is of the essence here," she said in a statement. "The National Marine Fisheries Service has concluded that coho salmon are in an 'extinction vortex.'"

Jeff Miller with the Center for Biological Diversity, a national activist group based in Arizona, claimed county supervisors "seem perfectly willing to sacrifice salmon habitat and put the interests of a select group of property owners and developers before the need to save an endangered species." He added that "the supervisors want more development in the San Geronimo Valley. We can't let that happen ... It could eliminate coho salmon from Marin County forever."

An audit several years ago indicated the county and the Marin Municipal Water District each were spending about $1 million a year on road, sediment, fish passage and related projects protecting San Geronimo Valley's troubled coho salmon run. In 2010, county spending over the previous five years totaled $5.3 million, and water district spending on salmon projects since 1997 totaled more than $9 million.